With Bury losing, it edged Stags into second place and opened a two-point gap between them and fourth place with just three games to go.
Shrimps keeper Barry Roche did all he could to deny Stags with some fine saves in a tense first half in which the home side deservedly went ahead through Jacob Mellis on the half-hour.
But it was a nervy game until two goals in three second half minutes ended Morecambe resistance as Krystian Pearce netted on 70 minutes and CJ Hamilton soon after.
Mal Benning then added a fourth near the end as Stags’ goal difference was given a huge boost for the final run-in.
The Mansfield side showed two changes as they brought midfield playmakers Jacob Mellis and Jorge Grant back in for Will Tomlinson and Alex MacDonald.
The visitors included ex-Stags defender Ritchie Sutton in the starting XI with former Mansfield striker Vadaine Oliver on the bench.
The game kicked off in bright, warm sunshine with a superb atmosphere.
Morecambe were first to show ambition as Collins fired a shot at Logan from 20 yards on three minutes.
But on five minutes it took a fine save from veteran Roche to deny Jones. Benning floated the ball in the centre and Jones met it with a powerful header from six yards that the keeper tipped over his bar.
Stags kept up the pressure when the corner was cleared and some great work from Pearce set up Mellis for a thunderous low shot that Roche managed to parry.
On eight minutes Preston’s lofted forward ball almost got Walker away, Roche dropping onto it at the striker’s feet.
The visitors weathered plenty of home pressure before, on 16 minutes, a poor Pearce clearance gifted the ball to Fleming for a low shot that deflected wide for a corner, from which Bennett headed over.
Soon after Walker had a low deflected shot for Stags that went straight to Roche.
A slip by Sutton saw Walker race away down the left on 21 minutes. But Roche was able to block his near post effort and Hamilton sent his follow-up wide.
Referee Kettle won no friends among home fans when he stopped a promising home attack to bring it back for a free kick and the boss were even louder when Lavelle jumped into Walker’s back to flatten him in the box on 24 minutes and no penalty was given.
Roche made another fine one-handed save to deny Bishop from 15 yards soon after as Stags turned up the heat, Roche forced the make a second stop as the loose ball continued to spin towards goal.
Fleming was booked for his off the ball coming-together with Mellis on 27 minutes and Benning was wide from the free kick.
Stags were finally and deservedly ahead on the half-hour mark. Benning looked set to cross from the left but instead squared a low pass to Mellis just inside the box and Roche was left rooted as he drilled a low finish inside the left post.
Kenyon’s foul on Bishop earned him a 36th minute yellow card, Grant curling the free kick onto the roof of the net.
More home pressure saw a Mellis shot deflect wide after a scramble in the box.
Pearce was added to the book for a foul on Collins in the final minute of the half.
In added time Roche pulled off the save of the game to stop Jones’ header creeping inside the post to his left from Hamilton’s cross as Stags went in with a more slender lead than they deserved for a fine half.
The Shrimps made a double change at the break, sending on Mingoia and Conlan for Kenyon and Sutton.
Roche was quickly back in action, using his legs to block a low shot from Grant on 48 minutes.
Mills was booked on 50 minutes for a nasty tackle on Benning that Stags felt should have been a red card.
Sweeney joined him for hacking down Collins on 53 minutes.
A great run from Hamilton down the left saw him set up Grant from the by-line but the midfielder was unable to divert the ball on target.
Walker was then wide as Morecambe struggled to clear their lines from a corner.
The visitors had a rare chance on 66 minutes as Logan had to clutch an Old header at his near post from a corner.
But the tension was eased four minutes later as Morecambe failed to clear Grant’s free kick, the ball falling to Pearce who made space and drilled a low finish inside the near post from eight yards.
Just three minutes later it was game, set and match as Hamilton cut inside from the right of the box from a pass by Mellis and smashed a low finish under Roche.
With five minutes to go Benning joined the scorer’s list with a crisp low shot from 25 yards that Roche failed to reach as it zipped inside the far post as Stags began to really enjoy their afternoon.
MANSFIELD: Logan; Sweeney, Pearce, Preston; Jones, Mellis, Bishop (Tomlinson 83), Grant (MacDonald 72), Benning; Walker (Rose 77), Hamilton. Subs not used: Smith, Atkinson, Turner, Hakeem.
MORECAMBE: Roche, Mills, Kenyon (Conlan HT), Old, Bennett, Fleming, Sutton (Mingoia HT), Lavelle, Mandeville, Cranston, Collins (Collins 72). Subs not used: Halstead, Ellison, McKay, Hedley.
REFEREE: Trevor Kettle of Rutland.
ATTENDANCE: 5,177 (107 away).
CHAD STAGS MAN OF THE MATCH: Jacob Mellis.